Continuous preparation method of cellulose fibers

Abstract

Disclosed is a continuous preparation method of cellulose fibers, in which a forming tension of 0.1 to 1.9 cN/dtex is applied to a fine solution stream obtained by extrusion through a spinneret plate and air gap cooling, then the fine solution stream is fed into a coagulating bath at a speed of 80 to 1000 m/min, a traction tension of 0.075 to 1.5 cN/dtex is continued to be applied to washed fibers in a water washing system behind the coagulating bath, and finally, the washed fibers are fed into a post-treatment system for continuous and efficient spinning of finished fibers at a speed of 80 to 1000 m/min.

What claimed is: 
     
       1. A continuous preparation method of cellulose fibers, wherein in the preparation method, a forming tension of 0.1 to 1.9 cN/dtex is applied to a fine solution stream obtained by extrusion through a spinneret plate and air gap cooling, then the fine solution stream is fed into a coagulating bath at a speed of 80 to 1000 m/min, a traction tension of 0.075 to 1.5 cN/dtex is continued to be applied to washed fibers in a water washing system after the coagulating bath, and finally, the washed fibers are fed into a post-treatment system for continuous spinning to obtain finished fibers, wherein a spraying direction of the coagulating bath is consistent with a running direction of the fine solution stream, the coagulating bath further comprises a coagulating bath water tank disposed at an outlet of tows, the coagulating bath water tank comprises a filament guide system, and the outlet of tows is disposed vertically extending downwards into the water tank, or is disposed along a liquid level of the water tank, or is disposed bending upwards along a liquid level of the water tank, or is disposed bending upwards from a position lower than a liquid level of the water tank, or is disposed higher than a liquid level of the water tank, so that the fiber tows passing through the coagulating bath are completely immersed, or partially immersed, or do not pass through the coagulating bath water tank; a soaking length of the fiber tows through the coagulating bath is 50 to 1500 mm; the coagulating bath water tank is provided with a filament guide system, a filament guide part of the filament guide system comprises one or more of driving double rollers, a single-roller combined filament separating roller, a rod and a hook; the driving double rollers or single roller is provided with a motor, and the rotating speed of the roller is the spinning speed; respective axis extension lines of the driving double rollers are intersected, and a number of winding turns of the tows on the driving rollers is not smaller than three; the filament guide system is installed below an outlet of the coagulating bath. 
     
     
       2. The continuous preparation method of cellulose fibers according to  claim 1 , wherein in the preparation method, a temperature of a spinning stock solution, a pore diameter of the spinneret plate and an air gap cooling condition are adjusted according to a speed of the coagulating bath, meanwhile, process conditions of the post-treatment system are adjusted, so that the cellulose fibers are subjected to tension suitable for all preparation stages, and the finished fibers are continuously spun by tows at a spinning speed of 80 to 1000 m/min. 
     
     
       3. The continuous preparation method of cellulose fibers according to  claim 2 , in the preparation method, a forming tension of 0.15 to 0.65 cN/dtex is applied to a fine solution stream obtained by extrusion through a spinneret plate and air gap cooling, then the fine solution stream is fed into a coagulating bath at a speed of 200 to 800 m/min, a traction tension of 0.1 to 0.6 cN/dtex is continued to be applied to washed fibers in a water washing system after the coagulating bath, and finally, the washed fibers are fed into a post-treatment system to obtain finished fibers. 
     
     
       4. The continuous preparation method of cellulose fibers according to  claim 1 , wherein the post-treatment system comprises two independent working sections for preparing cellulose filaments or cellulose staple fibers;
 the working section of the cellulose filaments comprises an oiling system and a drying section which are sequentially disposed, and then the treated fibers are wound into a filament cylinder finished product; the working section of the cellulose filaments comprises a pre-drying section, an oiling system and a main drying section which are sequentially disposed; 
 the working section of the cellulose staple fibers comprises a cutting section, a water washing section, an oiling system, a drying section and a packaging section which are disposed in sequence. 
 
     
     
       5. The continuous preparation method of cellulose fibers according to  claim 4 , wherein when the cellulose filaments are prepared, dried tows are subjected to a traction tension of 0.025 to 2.25 cN/dtex. 
     
     
       6. The continuous preparation method of cellulose fibers according to  claim 1 , wherein the spraying direction of the coagulating bath is parallel to the running direction of the fine solution stream. 
     
     
       7. The continuous preparation method of cellulose fibers according to  claim 1 , wherein a soaking length of the fiber tows through the coagulating bath is 100 to 350 mm. 
     
     
       8. The continuous preparation method of cellulose fibers according to  claim 1 , wherein a spinning stock solution is prepared by mixing, swelling and dissolving cellulose pulp and NMMO aqueous solution, an intrinsic viscosity of the cellulose pulp is not higher than 600 mL/g, and the cellulose is selected from pulp with single intrinsic viscosity and is also obtained by mixing cellulose pulp with difference in intrinsic viscosity; a cellulose content in the spinning stock solution is 5 to 15 wt %; and a temperature of the spinning stock solution is 90 to 130° C. 
     
     
       9. The continuous preparation method of cellulose fibers according to  claim 2 , wherein the pore diameter of the spinneret plate is 0.04 to 0.3 mm. 
     
     
       10. The continuous preparation method of cellulose fibers according to  claim 1 , wherein an adjustment range of an air gap cooling height in the air gap cooling condition is 10 to 200 mm, a humidity of a cooling air is absolutely dry 3 to 15 g/kg dry air, a temperature of the cooling air is 5 to 28° C., and a speed of the cooling air is 3 to 35 m/s. 
     
     
       11. The continuous preparation method of cellulose fibers according to  claim 2 , wherein the spinning speed is not smaller than the speed of the coagulating bath. 
     
     
       12. The continuous preparation method of cellulose fibers according to  claim 3 , wherein the spinning speed is higher than the speed of the coagulating bath. 
     
     
       13. The continuous preparation method of cellulose fibers according to  claim 3 , wherein the fine solution stream is subjected to the forming tension of 0.2 to 0.6 cN/dtex, the washed fibers are subjected to the traction tension of 0.15 to 0.55 cN/dtex, and tows are continuously spun into the finished fibers at the spinning speed of 200 to 800 m/min through the preparation method. 
     
     
       14. The continuous preparation method of cellulose fibers according to  claim 5 , wherein the dried tows are subjected to a traction tension of 0.06 to 1 cN/dtex. 
     
     
       15. The continuous preparation method of cellulose fibers according to  claim 1 , wherein the filament guide part is the driving double rollers. 
     
     
       16. The continuous preparation method of cellulose fibers according to  claim 8 , wherein the intrinsic viscosity of the cellulose pulp is 270 to 500 mL/g, the cellulose content in the spinning stock solution is 7 to 13 wt %, the temperature of the spinning stock solution is 100 to 125° C. 
     
     
       17. The continuous preparation method of cellulose fibers according to  claim 9 , wherein the pore diameter of the spinneret plate is 0.08 to 0.2 mm. 
     
     
       18. The continuous preparation method of cellulose fibers according to  claim 10 , wherein the adjustment range of the air gap cooling height in the air gap cooling condition is 35 to 125 mm, the humidity of the cooling air is absolutely dry 4 to 10 g/kg dry air, the temperature of the cooling air is 14 to 24° C., and the speed of the cooling air is 3.5 to 10 m/s.